Scale.



F. P. DUNN.

SCALE.

Arme/ 111011 fsLEu APR. 12, 1913.

1 ,249,927. Patented Dec. 11, 1917.

#Qa-o' Tnx/Trger -fulcrum 2, beam 3, load receiver UNITED sTATEs PATENT onirica.

FRANK 2P. DUNN, 0F ANDERSON, INDIANA, ASSIGNOR TO TOLEDO SCALE COMPANY, 0F

TOLEDO, OHIO, A CORPORATION OF NEW JERSEY.

SCALE.

Patented Dec. 11, 193'?.

Application filed April 12, 1913. Serial No. 760,733.

To all whom z't may concern.'

Be it known that I, FRANK P. DUNN, a citizen of the United States, residing at Anderson, in the county of Madison and State of Indiana, have invented. certain new and useful Improvements in Scales, of which the following is a specification.

My invention relates more particularly-to the class of beam scales in whibh a spring is employed as the means for offsetting the load or article to be weighed. Ordinarily these scales comprisea beam whichis a lever of the first order having the load receiver or platform upona one side of the fulcrum and the spring for counterbalance or offsetting the load at the other side of the fulcrum as well as a dial'and hand or other means for indicating the weight of the load or commodity being weighed. Perhaps the most serious defe'ct of scales of this character is that the spring is subject to variation with change of temperature, not only elongating with a rise of temperature but also becoming weaker or losing its tension, so that the beam moves a greater distance for the same load or weight inthe scale pan when it is warm than it does when cold and consequently the dial or other indicator reads larger in warm weather than in cold. It is the purpose of my invention tolprovide a manual adjustment for these variations in the tension of the sprin in scales of this character w1thout at t e Sametime introducing other` errors.

In the accompanying drawings I have shown, and in the followin specification, describe in detail a preferre form-of scale embodying my invention. It is to be understood, however, that the specic disclosure is for the purpose of exempls'fcation only, and that the scope of my invention is set forth in the following claims in which I have endeavored to distinguish it from the prior art so far as lmown.to me without, however, relinquishing any portion thereof.

In the accompanying drawings Figure 1 is a side elevation partly in section of the preferred form of scale, Fig. 2, an end elevation also partly in section, and Figs. 3, 4, and 5, enlarged details of the part with which my invention is more particularly concerned, in elevation and longitudinal and transverse section respectively. The base 1 of the scale, or scale pan 4, dial 5, and indicator hand 6 are or may being closed in a suitable casing?, mounted upon the end of the base. Any suitable means may be employed for operating the dial hand and I have shown for thispurpose a pinion 8 upon the shaft of the pointer :operated by a rack 9, pivoted at l0 to the end of the scale beam and held in mesh with the pinion by a guide 1l. The load offsetting or counterbalancing spring 12 is secured to the base at 13 and at is upper end is connected to an eye 14, adjustably mounted upon the scale beam. For the purpose of adjustably securing the eye 14, it is formed in an arm 15, extending through a slot 16 in .the end of the beam and provided at its other end with a nut 17', which is threaded upon a screw shaft 18 journaled in perfo# .toward or from the fulcrum of the beam.-

Beyond the lug 19 the screw shaft 18 is extended at 24 a sufficient distance to receive` 'the counterbalance weight 25, which is also in screw engagement with the shaft, but the thread is reversely inclined with reference to the thread upon which the nut 17 is mounted. The counter balance weight 25 is provided with a pin-26, which projects into a hole 27, in the lug 19 and permits the longitudinal movement of the counterbalance weight but prevents rotation thereof. 0bviously the counterbalance weight 25 i's also adjusted longitudinally of the beam by rotating the screw shaft but in a reverse direction to that of the spring attaching eye 14.

Whenever the tension of the spring changes from any cause such as change in the temperature, the scale may beprestored to correct reading by adjusting the point of attachment thereof towardl or from thefulcrum of the beam depending upon the nati-ifea' of the change in the spring. Thus, for eX- ample, when the temperature rises and the spring is correspondingly weakened, its counterbalancing effect may be increased by increasing the distance rof the point of attachment from the fulcrum of the beam;V

iin

and in case of a drop in the temperature a reverse adjustment may be made so that the 4scale may be maintained in proper condithe counterbalance is provided and its weight is so proportioned to that of the spring and connected parts that by moving it in the 'opposite direction, as provided for, it at all times balances the spring and connected parts, and thereby prevents any disturbance of the equilibrium of the scale due to the shifting of the parts.

I claim: o

1. In a scale of the class described, and in combination with the base, platform and load-receiver thereof, a spring attached at one end to the base, attaching means connected to the other end of the spring and mounted upon the beam and adjustable lengthwise thereof, a counterbalance weight likewise adjustable longitudinally of the beam, and means 'common to the" attaching means and the counterbalance weight for shifting them in opposite directions.

2. In a scale of the class described and in\ combination with the base platform and load receiver thereof, a spring attached 'at one vend to the base, attaching means connected to the other end of the spring Vand adjustable lengthwise of the beam,l a counterbalancel combination with the base, beam, and vgoods vreceiver thereof, a spring for osetting the Welght of the goods secured at'one end to the l base, a screw mounted upon the beam and L In a scale of the class described and in `combination with the base, beam, and load receiver thereof, a spring attached at one end to the base, a revoluble screw mounted upon the beam and having reversely thread- @ed screw portions, means for the' attachment of the end of the spring mounted upon one of said portions of the screw, and a counterbalance weight mounted upon the other portion of the screw.

5. In a scale of the class described and in combination with the base, beam, and load receiver thereof, a spring attached at one end to the base, a revoluble screw mounted upon the beam and having reversely threaded screw portions, means for attachment of the end of the spring mounted upon one of said portions of thescrew, a counterbalance Weight on the other portion, and a pin on the weight engaging a relatively stationary member to prevent the rotation ofthe counterbalance weight.

6. In a scale of the class described and in combination with the base, beam, and load receiver thereof, a spring attached at one end to the base, a pair of lugs 19 and 20, mounted upon the beam, a screw 18 revolu- 'bly mounted in the lugs, a finger piece 23 for turning the screw, the screw being formed with reversely threaded sections, a nut 17 carrying anc eye 14 to which said spring is attached, mounted upon one of the threaded portions of the screw and a counterbalance weight 25 having a pin 26 engaging the lug'l9,\.mounted upon the other section of the screw.

7. In a scale and in combination with the frame thereof, a beam having a slot therein, a spring secured at one end upon the frame, an arm extending through the slot in the beam to which the other end of the spring is secured, a manually movable member supported and arranged parallel to the beam, and means for connecting the arm to said movable member for adjustment longitudinally of the beam.

FRANK P. DUNN.

Witnesses R. E. KREIGH, A. lF. BnAnLY. 

